package com.lagou.config;

import com.lagou.pojo.Configuration;
import com.lagou.pojo.MappedStatement;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

import java.io.InputStream;
import java.util.Arrays;
import java.util.List;

public class XMLMapperBuilder {

    private static final List<String> SUPPORTED_STATEMENT_TYPES = Arrays.asList("select", "insert", "delete", "update");
    private Configuration configuration;

    public XMLMapperBuilder(Configuration configuration) {
        this.configuration = configuration;
    }

    public void parse(InputStream inputStream) throws DocumentException {

        Document document = new SAXReader().read(inputStream);
        Element rootElement = document.getRootElement();

        String namespace = rootElement.attributeValue("namespace");
        for (String type : SUPPORTED_STATEMENT_TYPES) {
            @SuppressWarnings("unchecked")
            List<Element> list = rootElement.selectNodes("//" + type);
            for (Element element : list) {
                String id = element.attributeValue("id");
                String resultType = element.attributeValue("resultType");
                String parameterType = element.attributeValue("parameterType");
                String sqlText = element.getTextTrim();
                MappedStatement mappedStatement = new MappedStatement();
                mappedStatement.setId(id);
                mappedStatement.setResultType(resultType);
                mappedStatement.setParameterType(parameterType);
                mappedStatement.setSql(sqlText);
                mappedStatement.setStatementType(type);
                String key = namespace + "." + id;
                configuration.getMappedStatementMap().put(key, mappedStatement);

            }
        }
    }


}
